GESTATIONAL DIABETES PRACTICE GUIDELINES 267 95 mg/dL (3.3–5.3 mmol/L) pre-meal and no greater than 120 mg/dL (6.7 mmol/L) 2 hours post-meal. Ample evidence shows that, as blood glucose rises, the risk of adverse perinatal out- come increases. In some studies, this relation- ship is linear. At fasting blood glucose levels of 95 mg/dL (5.3 mmol/L), the risk of a macrosomic infant is seven times greater than at 75 mg/dL (4.2 mmol/L). 10 At 105 mg/dL (5.8 mmol/L), the risk rises to 14 times greater than normal. It has also been noted that at blood glucose lev- els less than 75 mg/dL (4.2 mmol/L) intrauterine growth retardation may result. Setting t he tar- gets within these narrow parameters appears to be the most effective way to reduce risk of ad- verse perinatal outcome. The targets refer specif- ically to self-monitored blood glucose because of the need for continuous data on blood glu- cose level. These values are for the duration of the pregnancy regardless of the type of ther- apy. Normal HbA 1c should result from reaching these target blood glucose levels. HbA 1c may be assessed at the start of therapy as a base- line measure; however, it is generally not used in treatment. HbA 1c provides an approximation of the average blood glucose for 8–10 weeks before the test. An elevated HbA 1c (>1.0 per- centage points above the upper limit of normal) may suggest that the patient is actually an indi- vidual w ith pregestational diabetes (most likely type 2 diabetes) and had persistent hyperglycemia earlier than the time of screening. Under such circumstances, closer f etal evaluation for abnor- malities is advisable. Under most conditions the HbA 1c will be at or near normal since increased glycosylation of hemoglobin is not normally de- tected until blood glucose reaches an average of >140 mg/dL (7.8 mmol/L) over an extended pe- riod of time. Once in treatment, the HbA 1c would not be a sensitive indicator of mild hyperglycemia (120–150 mg/dL or 6.7–8.3 mmol/L) and, there- fore, is not generally used for clinical decision- making. Because some women with GDM will fast in order to lower their blood glucose (and thereby avoid insulin therapy), ketones should be measured and maintained at negative throughout the pregnancy. Monitoring One of the most perplexing problems in the treat- ment of GDM is the question of SMBG. Should the women with GDM be subjected to frequent monitoring (four to seven tests per day) from the time GDM is diagnosed? Reliance on SMBG for clinical decisions is almost self-evident. Certainly, patients treated with insulin are required to SMBG prior to each injection to adjust the dose. What about women on glyburide or diet only regimens? Regardless of the type of therapy, until hyper- glycemia is regulated and restored to euglycemia, rapid deterioration in BG is likely. As many as 50 per cent of those women with low-level hy- perglycemia at diagnosis (fasting <105 mg/dL or 5.3 mmol/L) may, despite dietary only in- terventions, experience persistent hyperglycemia (post-prandial >120 mg/dL or 6.7 mmol/L) that would go undetected without frequent SMBG. About 4 per cent of the women initially assigned to glyburide therapy require insulin to restore euglycemia. These women would go undetected without SMBG. Office visits, as often as every 2 weeks, would still be too infrequent to iden- tify persistent, meal-related hyperglycemia and to foster rapid ameliorative interventions. Therefore, SDM recommends that, independent of the type of therapy, SMBG be initiated in all patients. The frequency of testing is noted in Table 7.1. A meter with a memory is recommended in pregnancy. A number of studies have reported that reliability of patient SMBG reports is less than 20 per cent. To improve reliability of reporting, me- ters with onboard memories capable of storing the blood glucose test result with the corresponding time and date are necessary. Data can be accessed from these meters in two ways. The meter itself can be scrolled for individual values as well as Table 7.1 Frequency of testing Treatment Start Adjust Maintain Medical nutrition therapy 4/day 6–7/day 4/day Insulin Stages 4–6/day 6–7/day 6–7/day* * May reduce to 4/day after the 32nd gestational week. 268 PREGESTATIONAL AND GESTATIONAL DIABETES for a two week average. For more precise data, the meter can be connected to a personal computer and all data off-loaded. Evaluate for urine ketones until seven consecutive days of negative ketones are obtained and every other day thereafter. This will help detect starvation ketosis. Follow-up Specific to managing diabetes in pregnancy is the need to rapidly respond to hyperglycemia. Weekly phone contact plus office visits every 2 weeks un- til 36 weeks is recommended. Evidence suggests that, even as late as the thirty-sixth week, intro- ducing insulin or glyburide therapy can restore euglycemia and slow accelerated fetal growth due to maternal hyperglycemia. Close surveillance by SMBG is very important even as late as the 40th week. The decision in delivery time is based on four factors: • maternal hypertension (preeclampsia) • previous stillbirth • macrosomia • poor compliance and/or metabolic control Presence of any of these factors indicates need for early delivery (37–38 weeks). All other cases are encouraged to achieve spontaneous delivery at term. Postpartum maternal and infant follow-up Follow-up after delivery takes two courses for the mother. In instances where gestational dia- betes resolves itself to normal levels of glycemia immediately after birth, the mother should re- turn for screening by fasting plasma glucose be- tween 3 and 6 months following hospital dis- charge. Women with GDM are at increased risk for developing type 2 diabetes and should be mon- itored yearly for the development of the disease. Women with pregestational diabetes, and women with GDM whose blood glucose does not return to normal levels following delivery, should con- tinue to be treated to restore near-normal blood glucose levels. Women with GDM should be treated as type 2 diabetes unless their BG re- turns to normal. Infants of all patients are assessed at birth for APGAR score and glucose level. Infants are fed within 6 hours, and blood glu- cose levels are followed closely. Intravenous glu- cose may be necessary for 24–48 hours. Within 24 hours, additional evaluation includes gesta- tional age, evidence of macrosomic, congenital anomalies, and other diabetes-related morbidity such as polycythemia. Examination over the next several years encompasses evaluation of physio- logic, psychomotor, and psychological develop- ment. Gestational Diabetes Master DecisionPath Approximately 50 per cent of the women with GDM will begin treatment by medical nutri- tion therapy only, based on their diagnostic val- ues during the OGTT. Nutrition therapy encom- passes adopting a set of general rules to guide caloric intake and timing of meals (see the next section). If such rules fail to restore normo- glycemia, SDM recommends following the prin- ciples set out for general dietary management in diabetes and insulin resistance, specifically, to replace high- calorie foods with lower-calorie foods and drinks, to reduce portion sizes if the replacement fails, and to restrict certain foods if the reduction does not achieve lower BG. The re- maining women will require either glyburide or insulin based on entry BG and patient preference. The Master DecisionPath for gestational dia- betes, shown in Figure 7.3, contains the criteria for making decisions along with guidelines to as- sist in the implementation of each decision. The GESTATIONAL DIABETES MASTER DECISIONPATH 269 At Diagnosis* OGTT fasting plasma glucose Ͻ 95 mg/dL (5.3 mmol/L) At Diagnosis* OGTT fasting plasma glucose у 95 mg/dL (5.3 mmol/L) Medical Nutrition Therapy Stage Glyburide Stage If persistent hyperglycemia start Insulin Stage 3 Insulin Stage 3 (Mixed) RA/N–0–RA–N R/N–0–R–N If persistent midafternoon hyperglycemia or hypoglycemia, start Insulin Stage 4 Insulin Stage 4 (Basal/Bolus) RA–RA–RA–N or LA* R–R–R–N or LA* * Plasma glucose criteria for starting each therapy may be modified Insulins Comments R RA (lispro or aspart) N G 0 ϭ regular ϭ rapid acting ϭ NPH ϭ Glargine* ϭ none Dose shedule: AM–MIDDAY–PM–BEDTIME Continue with medical nutrition therapy throughtout all stages of therapy Glyburide is considered a pregnancy category B drug Some insulin analogs have not been tested in pregnancy; consider consulting a diabetes specialist before starting or maintaining insulin analogs during pregnancy. • • * OR OR Figure 7.3 Gestational Diabetes Master DecisionPath DecisionPath guides the practitioner regarding when to start each therapy and the criteria by which changes in therapy are made. Medical nu- trition therapy is part of the overall therapeutic strategy for gestational diabetes. In gestational di- abetes, the food and exercise plan is intended to lower blood glucose levels while avoiding excess weight gain or loss. A major problem is balanc- ing caloric intake with caloric expenditure. While the non-obese woman with GDM generally con- sumes adequate calories, the obese woman with GDM may take in excess calories compared with energy needs. A person who is obese may store three times more energy in the form of fat than the normal-weight individual. Obese individuals tend to have a diet with proportionately more fat and carbohydrate than the normal-weight individ- ual and tend toward less activity, contributing to the overall energy imbalance. In pregnancy, insulin resistance is already high. In GDM the normally high insulin resistance tends to be exaggerated. Obesity is also part of the metabolic syndrome and therefore further exag- gerates the effect of insulin resistance on BG, BP, and lipid abnormalities. Obesity related insulin re- sistance is probably due to changes that occur 270 PREGESTATIONAL AND GESTATIONAL DIABETES in the adipose tissue as cell size increases. It is believed that the number of insulin receptors re- mains stable while the cell surface area increases, effectively reducing the number of insulin recep- tors per unit of cell surface area. Simultaneously it has been demonstrated that, although insulin production increases in pregnancy, in GDM in- sulin production is still lower than that of age and weight matched women without GDM. This gives rise to a state of relative insulin deficiency in pregnancy, which i f left untreated results in hyperglycemia. 8 To reverse the course of hyperglycemia through medical nutrition therapy, the energy balance must shift to an increase in output with a decrease in input. An increase in output not only fosters more efficient use of calories but also begins to use en- ergy stored from the fat depot. The immediate result is improved insulin utilization as adipose tissue reduces in size. With a concomitant reduc- tion in stored energy as fat, the feedback loop favours improved glucose uptake with expended energy on the output side. If the changed caloric intake (from fat to carbohydrates and proteins) is coordinated with an increased level of activity, the imbalance that led to the obesity should be re- solved and a balanced or steady state re-instituted. This will help to overcome the insulin resistance and relative insulin deficiency. When GDM is treated with glyburide or insulin, medical nutrition therapy, which includes regular physical activity, is synchronized with the phar- macologic action of glyburide on the pancreatic β-cells or with action curves of exogenous insulin (see Chapter 3). The major challenge is not to al- low the additional endogenous insulin (from the action of glyburide) or the exogenous insulin to justify increased caloric intake in excess of that needed to respond to energy output. This requires adjusting the timing of food, not the amount. The same caloric intake should be maintained to en- sure appropriate growth and development of the fetus as would have been recommended in the ab- sence of either pharmacologic agent. Administra- tion of glyburide or exogenous insulin necessitates spreading food intake rather than adding calories. This will require trial and error. Selecting a treatment regimen Staged Diabetes Management relies on blood glucose data gathered during diagnosis and ini- tial therapy to characterize the underlying hy- perglycemia of pregnancy and to rapidly select a therapy to ensure an orderly progression to euglycemia. In this manner, SDM bases its ap- proach on the scientific rationale for treatment. The underlying principle in managing GDM is to expeditiously initiate therapy to forestall the effect of maternal hyperglycemia on accelerated fetal growth. Gestational diabetes is generally de- tected during the third trimester at a point when human placental lactogen reaches its highest lev- els. In GDM, this allows a very short time to identify the correct treatment and intensify the therapy to re-establish normal blood glucose lev- els (60–120 mg/dL or 3.3–6.7 mmol/L). Aware that any period of hyperglycemia, however brief, may contribute to excessive fetal growth, SDM seeks to reduce the risk of accelerated fetal growth through restitution of normoglycemia. The goal of SDM is to use the earliest possible criteria to determine the most efficacious therapy. Since the OGTT is t he basis of diagnosis in GDM, using the fasting plasma glucose value determined at the start of this test provides a good source for selecting initial therapy. At diagnosis, when the OGTT fasting plasma glucose is less than 95 mg/dL (5.3 mmol/L), medical nutrition therapy has a good chance of restoring euglycemia if followed rigorously. When the OGTT fasting plasma glucose level is ≥95 mg/dL (5.3 mmol/L) at diagnosis, the risk of persistent hyperglycemia increases significantly. At this point, initiating pharmacologic therapy is recommended to prevent further deterioration of blood glucose levels. 18 The choice of therapy is between glyburide and insulin. So long as the fasting BG is less than 150 mg/dL (8.3 mmol/L), there is a chance that glyburide will be effective. Above this point, glyburide cannot effectively lower BG to near- normal levels. If the BG is above the criteria for glyburide or if the newness of this therapy presents any doubts in its efficacy, then insulin therapy should be initiated. While two- and three- injection regimens can be effective, Stage 4 is the GESTATIONAL DIABETES MASTER DECISIONPATH 271 Table 7.2 Timelines to reach management goals Stage Time Medical nutrition therapy 7–14 days Glyburide stage 10–14 days Insulin Stage 3 14–21 days Physiologic Insulin Stage 4 14–21 days most physiologic and therefore likely to achieve tight control using the smallest amount of insulin. Once the therapy is selected SMBG is used to evaluate its continued efficacy. The Master DecisionPath for GDM contains the sequence of therapies to try if the first therapy fails to achieve glycemic targets. The patient, us- ing SMBG, provides the clinician with the data on which the efficacy of the initial and subsequent therapies is assessed. The criteria for moving from one stage to the next are based principally on identification of patterns of abnormal blood glu- cose values. For example, movement from MNT stage to glyburide is based on SMBG fasting be- tween 95 mg/dL and 150 mg/dL (5.3 mmol/L and 8.3 mmol/L) or two hour post-prandial between 120 mg/dL and 180 (6.7 mmol/L and 10 mmol/L) occurring twice within a week. Similarly, if the patient is in Stage 3 and experiences persistent mid-afternoon hypoglycemia and/or late afternoon hyperglycemia, movement to Stage 4 is recom- mended to provide greater flexibility in insulin adjustment. Throughout all therapies, a food plan is maintained. Refer to Table 7.2 for approximate timelines to reach management goals. Patient education Initiating treatment for gestational diabetes in- cludes an orientation/education program designed to help the individual recognize the importance of diabetes in pregnancy and to institute the pre- scribed regimen immediately (see Figures 7.4 and 7.5). This is required because, unlike all other forms of diabetes, during pregnancy the window for effective intervention during which achieving euglycemia is an effective means of tertiary prevention (i.e. prevention of compli- cations) diminishes. During orientation, all pa- tients (regardless of treatment modality) are taught SMBG techniques and given dietary instructions. All women are also taught insulin administra- tion techniques. The objective of therapy is to rapidly achieve euglycemia (fasting blood glu- cose averaging below 95 mg/dL (5.3 mmol/L)) and post-prandial blood glucose averaging be- low 120 mg/dL (6.7 mmol/L). Concurrently, pa- tients at ideal body weight must gain weight during pregnancy to ensure appropriate growth and development of the fetus. Obese individuals’ weight management must consider fetal growth and development and maternal well-being (specif- ically pregnancy induced hypertension). During follow-up visits education should reinforce treat- ment goals and emphasize the points f ound in Figure 7.5. Medical nutrition therapy All persons with GDM require a food and activity plan as part of the initial and follow-up treatment for hyperglycemia. If the individual is initially or subsequently placed on pharmacological ther- apy, she will continue to maintain virtually the same nutritional therapy as if she were following a food plan alone. The term food plan (or medi- cal nutrition therapy) encompasses the total daily required caloric intake (a combination of meals and snacks). The first step in determining the ap- propriate food plan is to complete the physical examination and, where possible, to consider con- sultation with a dietitian. The variables that deter- mine appropriate food plan and eventually dietary compliance go well beyond the current physical well-being of the individual. Psychosocial issues and economics must be considered. Thoroughly assess the patient’s readiness and ability to fol- low a food plan to re-establish a balance between caloric input and energy output. Discussing the overall Gestational Diabetes Master DecisionPath, providing the patient with choices, and clearly es- tablishing the metabolic goals are necessary steps in this process. 272 PREGESTATIONAL AND GESTATIONAL DIABETES GCT and OGTT results Diabetes treatment (SMBG target) Medical history including previous GDM, HTN Medications HbA 1c /ketones SMBG targets Diabetes education indicated Obtain Referral Data • • • • • • Established Education Plan Assessment Height/weight (BMI)/BP Risk factors (family history, obesity, ethnicity, previous GDM) Diabetes knowledge/skills Psychosocial issues (denial, anxiety, depression) Economic/cultural factors Readiness to learn/barriers to learning Lifestyle (work, school, food and exercise habits) Tobacco/alcohol use Support systems Health goals • • • • • • • • • • Goals SMBG/HbA 1c within target range Achieve self-management knowledge/skills/ behavior (SMBG, medications, nutrition, exercise) • • Plan Teach initial education topics Establish behavior goals with patient (exercise, nutrition, medications, monitoring) • • Are goals being met? YES Is any additional education needed? NO Summarize progress; document and communi- cate in writing to referral source Follow-up Education: every 2–4 weeks Behavior Goals Goals must be specific, reasonable, and measurable Document goals for the patient record and give copy to patient Encourage rewards for progress • • • Consider addressing adherence issues, updating education plan, or setting new behavior goals; document and communicate education delivered and new goals in writing to referral source See Self-Management Adherence and Psychosocial Assessment Follow-up Education: 2–4 weeks Review specific topics; document and communicate education delivered in writing to referral source See Diabetes Education Topics Follow-up Education: within 3 months YES NO Figure 7.4 Gestational Diabetes Education Medical Nutrition Therapy/Start Establish an appropriate food plan based on an assessment of the individual’s current food in- take (see Figure 7.6). A food history or three day food record, with confirmation by another family member (if possible), provides adequate approx- imations of caloric intake. Choice of food plan depends substantially on the resources of the pa- tient and the physician. The dietary information GESTATIONAL DIABETES MASTER DECISIONPATH 273 Initial Visit General Information Explain gestational diabetes, pathophysiology Discuss risk factors (obesity, family history, age, multiparity, ethnicity) Discuss risks to mother and baby (macrosomic or large-for-gestational-age infant) Review treatment plan and Master DecisionPath Discuss target goals for SMBG and weight Teach SMBG with memory meter and record-keeping Hypoglycemia Daily schedule Urine ketone monitoring Alcohol, medications, and drugs Emergency phone numbers • • • • • • • • • • • Add for Insulin Users Insulin injection technique Daily schedule Interaction of food, exercise, and insulin Insulin action and insulin storage Medical identification Syringe disposal Driving and diabetes • • • • • • • Follow-up Visits General Information Review first visit topics Review SMBG/urine ketone results Check meter accuracy, compare record book and download data Lifestyle issues (home, work, school) Hypoglycemia/hyperglycemia Review use of glucagon for hypoglycemia Illness management • • • • • • • Add for Insulin Users Review technical skills in SMBG and injections Insulin adjustment using SMBG patterns Insulin site rotation and problems Travel/schedule changes and the effect on insulin • • • • Add as Needed Healthy lifestyles, weight management Benefits and responsibilities of self-care Emergencies Hygiene Stress management Travel/schedule changes Community resources Psychological adjustments Food stamps • • • • • • • • • Postpartum Visit Review SMBG since delivery Discuss risk factors for developing type 2 diabetes (family history, obesity, previous GDM, multiparity, GDM in future pregnancies) Birth control Preconception planning for future pregnancies • • • • Figure 7.5 Gestational Diabetes Education Topics provided here supports the initial purpose of the food plan – to reduce blood glucose to near- normal levels. Food planning and nutrient composition. Individualize the food plan. The percentage of car- bohydrates, protein, and fat varies depending on the patient’s usual food intake. Controlling car- bohydrate intake is especially important since the nutrient contributes significantly to blood glucose level. A sample food plan is shown in Figure 7.6. Modifications in nutrient composition will be re- quired for patients with such conditions as hyper- lipidemia and/or hypertension (pre-eclampsia). Exercise. Recall that the importance of exercise in restoring a balance between food intake and energy expenditure is paramount in managing the non-pregnant woman with diabetes. Developing an exercise plan for pregnancy begins with as- sessing the patient’s fitness. A registered dietitian or exercise specialist often can be very helpful. In their absence, common sense plays a major role. Exercises should be comfortable, frequent, con- sistent, and reasonable based on the limitations of pregnancy. Fitting exercise into the lifestyle of most patients requires innovation. Some exercises can be done while sitting, standing, and even lying down. In pregnancy, exercise should be carefully 274 PREGESTATIONAL AND GESTATIONAL DIABETES At Diagnosis OGTT fasting plasma glucose Ͻ95 mg/dL (5.3 mmol/L) History, physical exam, and laboratory evaluation by clinician Start Medical Nutrition Therapy Assessment Food history or 3 day food record (meals and snacks with times and portions) Nutrition adequacy Weight gain/change Exercise times, duration, and type Fitness level (strength, flexibility, endurance) Alcohol use Vitamin and mineral supplement • • • • • • • Goals Good pre-natal nutrition Proper weight gain based on BMI SMBG within target range Negative ketones • • • • Plan Two carbohydrate choices at breakfast and consistent bedtime snack Set meal and snack times Set consistent carbohydrate intake at meals and snacks to meet BG targets (see sample food plan) Encourage regular exercise based on usual activity prior to pregnancy • • • • Refer for diabetes and nutrition education within 48 hours Follow-up Medical: Nutrition: Education: phone within 3 days to review SMBG, urine ketones, and food records, then office visit within 1–2 weeks every 2–4 weeks every 2–4 weeks Move to Medical Nutrition Therapy/Adjust SMBG Targets All values within target range Pre-meal and bedtime: 60–95 mg/dL (3.3–5.3 mmol/L) Post-meal: Ͻ120 mg/dL (6.7 mmol/L) 2 hours after start of meal; Ͻ140 mg/dL (7.8 mmol/L) 1 hour after start of meal Urine Ketones Target • • • • Negative SMBG Frequency Test 7 times/day; before and 1–2 hours after start of meals and at bedtimes Minimum 4 times/day; fasting and 1–2 hours after start of meals • • Urine Ketone Monitoring • Test every AM for 1 week if negative, then every other AM thereafter Weight Gain Guidelines % DBW 90% 90–120 Ͼ120 BMI Ͻ19.8 19.8–26 Ͼ26 GAIN 28–40 lb (13–18 kg) 20–35 lb (9–16 kg) 15–25 lb (7–11 kg) Target weight gain for significantly obese women (BMIϾ29 kg/m 2 ): approximately 15 lb (6.8 kg) Sample Food Plan MEAL CHO MEAT/SUB ADDED FAT Breakfas t Snack Lunch Snack Dinner Snack 2 1–2 3–4 1–2 3–4 1–2 0 2–4 0 2–3 0–1 0–1 0–1 0–1 1–2 0–1 1–2 0–1 1 CHO ϭ 1 carbohydrate serving ϭ 15 g carbohydrate; 60–90 calories 1 Meat/Sub ϭ 1 oz serving (28 g) ϭ 7 g protein; 5 g fat; 50–100 calories 1 Added Fat ϭ 1 serving ϭ 5 g fat; 45 calories Vegetables ϭ 1–2 servings/day with each meal; not counted in plan • • • • Figure 7.6 Gestational Diabetes Medical Nutrition Therapy/Start GESTATIONAL DIABETES MASTER DECISIONPATH 275 monitored. Preterm labour is a risk in 10–15 per cent of these women. Exercise that stimulates labour should be avoided. Exercise should also take into account seasons. Walking outdoors is fine on days when the weather is good, but walk- ing indoors in shopping centers or a health club is best for inclement weather. One way to rein- force the benefits of exercise and activity is to use SMBG. The next section details how this method of monitoring may support feedback for exercise. Glucose monitoring. To determine if the nu- trition and exercise goals are being met, self- monitoring of blood glucose should be an inte- gral part of treatment. During the start treatment phase when data are being collected to determine whether medical nutrition therapy and increased exercise are reasonable choices, SMBG must oc- cur at least four to six times each day. A sched- ule of before and 2 hours after the start of each meal provides adequate information on fasting glucose levels as well as post-meal recovery. This should be combined with testing before and after exercise (at least twice during the initial treatment phase). Testing using a memory-based meter is the only certain way to ensure reliable, accurate data. Where memory meters are unavailable, attempt to have a third party witness testing. Whether a memory meter or another method of verification is used, do not employ any technique as punishment. Patients are likely to fabricate results to please the provider. For some clinicians, using glycosylated hemo- globin (HbA 1c ) in place of SMBG has become routine practice. In gestational diabetes, HbA 1c may be used at the time of diagnosis as a basis to assess overall glycemic control up to this point and to determine whether the patient is at high risk for type 2 diabetes. It should not be used thereafter since it provides no ad- ditional information for clinical decision-making in GDM.HbA 1c measures glycosylation of the hemoglobin in red blood cells over their lifetime (∼120 days). As blood glucose concentrations rise, the per cent of hemoglobin that is glyco- sylated increases. Measuring this fraction makes it possible to estimate t he overall blood glucose control for the previous 8–10 weeks (taking into account the half-life of a red blood cell). In GDM, daily monitoring of blood glucose, not HbA 1c , is the basis of evaluating the effectiveness of treatment. During the initial treatment period, all SMBG data should be reviewed weekly. If two unex- plained elevations in fasting blood glucose exceed 95 mg/dL (5.3 mmol/L) or two post-prandials exceed 120 mg/dL (6.7 mmol/L), consider start- ing glyburide or insulin. If the elevations are due to excessive carbohydrate intake, reinforce the importance of following the prescribed food plan. A follow-up visit w ithin 1–2 weeks of the ini- tial visit should be made. At that time review baseline data (SMBG). If glycemic targets have not been achieved by the follow-up visit, rein- force principles of medical nutrition therapy and consider starting pharmacological therapy. A systematic approach to nutrition management of GDM begins with collecting data on which the initial interventions will be based. Whether carried out by a registered dietitian or a physician, the information required is the same. It is recognized, however, that where referral is not possible, the physician and nurse may be required to perform this assessment. Evaluate for: • Diabetes treatment regimen (medical nutrition therapy, or medical nutrition therapy with insulin) • Medical history – medications that affect diet prescription such as hypertensive medi- cations, lipid lowering medications, gastroin- testinal medications, and so on • Laboratory data: glucose challenge test and oral glucose tolerance test results • Provider goals for patient care: target blood glucose, method and frequency of blood glu- cose monitoring or plans for instruction • Medical clearance for patient to exercise and/or other pertinent information related to exercise, i.e., limitations for exercise, reasons patient cannot exercise 276 PREGESTATIONAL AND GESTATIONAL DIABETES Assessing obesity. The initial visit to deter- mine the appropriate nutrition intervention should include a very careful and documented means to assess body mass index (BMI). Measuring BMI is frequently used because it permits adjustment of nutrient intake for appropriate weight gain during pregnancy. A table for calculating BMI is located in the Appendix, Figure A.5. The recommended weight gain in pregnancy based on BMI is shown in Table 7.3. Once the BMI has been determined, assess whether data are sufficient (diabetes treatment regimen, laboratory data, medications, medical history, and overall therapeutic goals) to develop a food plan. With sufficient data on hand a thorough diet history should include past experience with food plans, other diet restrictions, weight history and recent weight change, weight goals, appetite, eating or digestion problems, eating schedule, who prepares meals, typical day’s food intake (to be evaluated for approximate calories and nutrient composition, other nutritional concerns, and frequency and timing of meals), frequency and choices in restaurant meals, alcohol intake, and use of vitamins or nutritional supplements. Data from the diet history should be com- bined with exercise habits and physical activity level. (What activities does the patient do? Does the patient exercise regularly? What limitations does the patient have that would hinder/prevent exercise? Is the patient willing to become or inter- ested in becoming more physically active?) Psy- chosocial/economic issues must also be assessed. During the visit include in the review informa- tion about the patient’s living situation, cooking Table 7.3 Recommended weight gain during pregnancy Pre-pregnancy BMI Weight Gain (%DBW) <90% <19.8 28–40 lb (13–18 kg) 90–120% 19.8–26 20–35 lb (9–16 kg) >120% >26 15–25 lb (7–11 kg) Target weight gain for significantly obese women (BMI >29 kg/m 2 ) is approximately 15 lb (6.8 kg). facilities, finances, educational background, em- ployment, and ethnic, religious, and belief con- siderations. While most women experience some mild anxiety when they learn they have gesta- tional diabetes, most women adjust rapidly and will follow the treatment plan. Emphasis on tight control to avoid complications should be balanced with sensitivity to “self-blame.” If persistent non- adherence occurs, consider immediate counseling services. If the patient is to start medical nutrition therapy alone to improve glycemic control, it is espe- cially important not to omit SMBG. Frequently, SMBG is used less often with such patients. This places the patient and health care professional at an enormous disadvantage. Without SMBG data it is almost impossible for the patient or profes- sional to have adequate data to determine how well the nutrition therapy is working. Therefore, it is important to assess patient knowledge of target blood glucose ranges, review blood glucose test- ing method and frequency of testing if needed, and review blood glucose records for incidence of hyperglycemia and number of blood glucose values in the target range. Next, to determine goals, develop a plan that includes a combination of patient and health care team goals related to diabetes management, such as target blood glucose levels (lower in pregnancy), weight, and blood pressure (if pre- eclampsia). The nutrition prescription should in- clude a food plan individualized to the patient based on diet history, f ood patterns and prefer- ences, and other collected data, as well as so- cioeconomic issues, ethnic/cultural and religious practices, and lifestyle. Determine caloric requirements. Table 7.4 shows how to estimate caloric requirement. Next, evaluate the macronutrient composition of the food plan. Food plan should be individualized according to a person’s lifestyle and eating habits as well as concurrent medical conditions. (In preg- nancy the concerns are to balance fetal nutrition with maternal weight gain. To avoid possible star- vation, check ketones daily.) Once determined, the food plan will remain fairly constant. Specifically, the total caloric plan [...]... diagnosis), evaluation for both macrosomic and small-for-gestational-age fetuses begins at the 28th gestational week This consists of examination by ultrasound to calculate the femur/abdomen ratio, head/abdominal circumference ratio, and estimated fetal weight for a given gestational age The measurements are repeated at 32nd to 33rd gestational week and the 37th gestational week If the tests indicate... an opportunity to review behaviours that may be dysfunctional to the overall treatment goal References 1 Buchanan TA Pregnancy in preexisting diabetes In: Diabetes in America 2nd Ed, 1995: 71 9 73 3 2 Benjamin E, Winters D, Mayfield J and Gohdes D Diabetes in pregnancy in Zuni Indian women Diabetes Care 1993; 16: 1231–1235 3 Coustan DR Gestational diabetes In: Diabetes in America 2nd Ed, 1995: 70 3 71 7... with diabetes tend to be hospitalized most frequently for management of a chronic complication related to diabetes However, they are also hospitalized for acute complications, such as diabetic ketoacidosis, and non -diabetes- related events Special provisions are necessary and are discussed in Chapter 10 8 Macrovascular Disease While significant attention is focused on the microvascular complications associated... hypertension has different prevalence rates due to ethnicity For example, American Indians have a lower prevalence of hypertension than Caucasians, whereas African-Americans have a higher prevalence. 17, 18 For the most part, the etiology of essential hypertension is poorly understood, yet its association with cardiovascular disease has been known for decades Studies have shown a statistically significant relationship... Hypertension also directly affects the arterial vasculature expressed as macrovascular disease with specific emphasis on the coronary arteries Insulin resistance, hypertension, and cardiovascular disease The pathway from insulin resistance development of cardiovascular disease is through such inter-mediaries as dyslipidemia, elevated blood pressure, inelastic arteries, inflammatory disease, and coagulation abnormalities... compared with regular insulin that was accompanied with high patient satisfaction with the analog.21 Currently, there are no well controlled studies demonstrating the safety and efficacy of aspart and long-acting analogue insulins during pregnancy Aspart, glulisine, glargine, and detemir are considered pregnancy category C drugs (based on United States Food and Drug Administration classification) and should... the debate over whether to routinely monitor CRP levels continues, the question to the clinician remains Since Staged Diabetes Management relies on a “treat-to-target” approach, it does not recommend routine CRP determinations for all patients because of the current absence of a clearly defined CRP target Individuals with diabetes and/or metabolic syndrome are already at increased cardiovascular risk,... thus aggressive management of lipids and HTW should already be undertaken CRP determinations should be considered in those patients at highest risk of cardiovascular disease Note, that this recommendation may change as the role of markers of inflammation and potential treatment targets become clearer INSULIN RESISTANCE, HYPERTENSION, AND CARDIOVASCULAR DISEASE 2 97 Prevention of cardiovascular disease... requiring the assistance of a diabetes specialist Confounding the presence of complications is the fivefold to eightfold greater risk of requiring hospitalization Many of the complications of diabetes are preventable or at least their progress Staged Diabetes Management: A Systematic Approach (Revised Second Edition)  2006 Matrex ISBN: 0-4 7 0-8 6 576 -X can be slowed Poor glycemic control, hypertension and dyslipidemia... individual with 292 PREGESTATIONAL AND GESTATIONAL DIABETES diabetes may feel the physician will make all decisions related to care and the patient should be passive Alternatively, the physician may feel the patient should be the person to make daily decisions about diet, insulin, and exercise Co-empowerment is an agreement between the patient and health care team that delineates the responsibilities and . individual values as well as Table 7. 1 Frequency of testing Treatment Start Adjust Maintain Medical nutrition therapy 4/day 6 7/ day 4/day Insulin Stages 4–6/day 6 7/ day 6 7/ day* * May reduce to 4/day. demonstrating the safety and efficacy of aspart and long-acting ana- logue insulins during pregnancy. Aspart, gluli- sine, glargine, and detemir are considered preg- nancy category C drugs (based. error. Selecting a treatment regimen Staged Diabetes Management relies on blood glucose data gathered during diagnosis and ini- tial therapy to characterize the underlying hy- perglycemia of pregnancy and